Next story in Space

Over the next few nights, the moon will be well placed for observation as it moves towards full moon on Sunday night.

This month's full moon is special, because it is the Harvest Moon in the Northern Hemisphere. Because of the location of the sun, Earth, and moon this month, the nearly full moon will appear low in the southeastern sky for several nights in a row, which traditionally has allowed farmers an extension of daylight during the critical time of year when they are harvesting their crops.

It is moving towards full moon on the night of Sept. 11 and hits its peak on Monday, Sept. 12. To avoid confusion, astronomers often refer to a night by its "double-date," in this case "Sept. 11/12."

The exact time of full moon will be 5:27 a.m. EDT (0927 GMT) on Sept. 12.

Phases of September's moon
Currently, the moon is in its waxing gibbous phase and not yet completely full. This sky map of the September's waxing gibbous moon shows how it will appear to skywatchers at mid-northern latitudes this week.

The first quarter and full moon, like the last quarter and new moon, are instantaneous events, marking the exact times when the geometry of the sun and moon, centered on the Earth, forms exact right angles. [ Infographic: Phases of the Moon Explained ]

The seven-day spans between the four lunar phase markers are named for the shape the moon takes, crescent or gibbous, and whether the moon is growing (waxing) or shrinking (waning). Here's a rundown of the order of moon phases and the angles of the sun and moon, with respect to Earth:

Most people know what "crescent" means but are puzzled by "gibbous." It comes from an old Latin word gibbus meaning "hump," and refers to the hump shape that the moon assumes during this phase.

A lunar lover's delight
Some people may take the moon for granted, but it is worthy of a lot more attention from skygazers.

Take a careful look over the next few nights and you'll be surprised at how much detail you can see on the moon with your unaided eye. In fact, you can see more detail on the moon with your naked eye, than can be seen on Mars with the finest telescopes on Earth.

Use an ordinary binocular or small telescope and you’ll be able to see a number of the famous craters on the moon. These are named for the great astronomers of the past; only the craters named for the Apollo astronauts honor living people.

The most striking feature of the waxing gibbous moon is the bright band along its equator which divides it into two darker halves. This band is punctuated by the large crater Copernicus 58 miles (93 kilometers) in diameter. Examine this crater in a telescope to appreciate its complex terraced walls. [ Photos: Our Changing Moon ]

Look towards the northern edge of the moon for the dark-floored crater Plato, 63 miles in diameter, and toward the southern edge for the brilliant Tycho 53 miles in diameter. Plato is close to the arcing "shoreline" of the Sinus Iridum, the "Bay of Rainbows."

The ancient astronomers who named the plains of the moon "seas" and "bays" had no idea that it was an airless, waterless wilderness. Tycho is one of the youngest craters on the moon, a mere 100 million years old, and is the origin of a complex system of rays stretching half way around the moon.

With these as your guides, look more closely for the gigantic walled plain of Gassendi 68 miles in diameter on the northern "shore" of the Mare Humorum (which was perfectly lit by the rising sun on Sept. 8). Observers with telescopes can see the complex system of rilles which crisscross its floor. On the moon, a "rille" is a crack in the surface where overlying material has collapsed.

The sun will rise over the Aristarchus, which is small in diameter (about 25 miles), but is the brightest area on the whole moon, on Friday night. Associated with Aristarchus is a huge mountain massif broken up by a winding valley, the Vallis Schröteri. Aristarchus is another fairly "young" crater, only 450 million years old and, like Tycho, is the origin of a complex ray system.

It’s interesting to use Wikipedia to explore the lives of the astronomers who have had craters named after them. Some, like Nicolas Copernicus and Tycho Brahe, are well known; others, like Pierre Gassendi, less so.

Then, for the next few nights, simply kick back and enjoy the beauty of the Harvest Moon, rising evening after evening in the east, and filling the late summer evenings with golden light.

This story was updated to correct the timing of September's Harvest Full Moon, which occurs at 5:27 a.m. ET on Monday, Sept. 12.

Southern stargazing

Stars, galaxies and nebulas dot the skies over the European Southern Observatory's La Silla Paranal Observatory in Chile, in a picture released on Jan. 7. This image also shows three of the four movable units that feed light into the Very Large Telescope Interferometer, the world's most advanced optical instrument. Combining to form one larger telescope, they are greater than the sum of their parts: They reveal details that would otherwise be visible only through a telescope as large as the distance between them.
(Y. Beletsky / ESO)
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A balloon's view

Cameras captured the Grandville High School RoboDawgs' balloon floating through Earth's upper atmosphere during its ascent on Dec. 28, 2013. The Grandville RoboDawgs’ first winter balloon launch reached an estimated altitude of 130,000 feet, or about 25 miles, according to coaches Mike Evele and Doug Hepfer. It skyrocketed past the team’s previous 100,000-feet record set in June. The RoboDawgs started with just one robotics team in 1998, but they've grown to support more than 30 teams at public schools in Grandville, Mich.
(Kyle Moroney / AP)
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Spacemen at work

Russian cosmonauts Oleg Kotov, right, and Sergey Ryazanskiy perform maintenance on the International Space Station on Jan. 27. During the six-hour, eight-minute spacewalk, Kotov and Ryazanskiy completed the installation of a pair of high-fidelity cameras that experienced connectivity issues during a Dec. 27 spacewalk. The cosmonauts also retrieved scientific gear outside the station's Russian segment.
(NASA)
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Special delivery

The International Space Station's Canadian-built robotic arm moves toward Orbital Sciences Corp.'s Cygnus autonomous cargo craft as it approaches the station for a Jan. 12 delivery. The mountains below are the southwestern Alps.
(NASA)
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Accidental art

A piece of art? A time-lapse photo? A flickering light show? At first glance, this image looks nothing like the images we're used to seeing from the Hubble Space Telescope. But it's a genuine Hubble frame that was released on Jan. 27. Hubble's team suspects that the telescope's Fine Guidance System locked onto a bad guide star, potentially a double star or binary. This caused an error in the tracking system, resulting in a remarkable picture of brightly colored stellar streaks. The prominent red streaks are from stars in the globular cluster NGC 288.
(NASA / ESA)
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Supersonic test flight

A camera looking back over Virgin Galactic's SpaceShipTwo's fuselage shows the rocket burn with a Mojave Desert vista in the background during a test flight of the rocket plane on Jan. 10. Cameras were mounted on the exterior of SpaceShipTwo as well as its carrier airplane, WhiteKnightTwo, to monitor the rocket engine's performance. The test was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventual commercial space tours.

Red lagoon

The VLT Survey Telescope at the European Southern Observatory's Paranal Observatory in Chile captured this richly detailed new image of the Lagoon Nebula, released on Jan. 22. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of 11 public surveys of the sky now in progress using ESO telescopes.
(ESO/VPHAS team)
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Fire on the mountain

This image provided by NASA shows a satellite view of smoke from the Colby Fire, taken by the Multi-angle Imaging SpectroRadiometer aboard NASA's Terra spacecraft as it passed over Southern California on Jan. 16. The fire burned more than 1,863 acres and forced the evacuation of 3,700 people.
(NASA via AP)
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Where stars are born

An image captured by NASA's Spitzer Space Telescope shows the Orion Nebula, an immense stellar nursery some 1,500 light-years away. This false-color infrared view, released on Jan. 15, spans about 40 light-years across the region. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also can detect stars still in the process of formation, seen here in red hues.
(NASA / JPL-Caltech)
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A long, long time ago...

This long-exposure picture from the Hubble Space Telescope, released Jan. 8, is the deepest image ever made of any cluster of galaxies. The cluster known as Abell 2744 appears in the foreground. It contains several hundred galaxies as they looked 3.5 billion years ago. Abell 2744 acts as a gravitational lens to warp space, brightening and magnifying images of nearly 3,000 distant background galaxies. The more distant galaxies appear as they did more than 12 billion years ago, not long after the Big Bang.
(NASA / NASA via AFP - Getty Images)
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Frosty halo

Sun dogs are bright spots that appear in the sky around the sun when light is refracted through ice crystals in the atmosphere. These sun dogs appeared on Jan. 5 amid brutally cold temperatures along Highway 83, north of Bismarck, N.D. The temperature was about 22 degrees below zero Fahrenheit, with a 50-below-zero wind chill.